Tolerances for engine components and other equipment parts have tightened and continue to tighten. The benefits of reducing tolerances include improved emission control and efficiency, resulting in improved regulatory compliance and marketability. However, reducing tolerances places increased focus on maintaining the cleanliness of the working fluids. For example, requirements for particle filtration continue to rise for fluids such as engine lubricants.
One of the methods for fluid cleanliness control is utilization of the spin on filters of various efficiencies. Such filters typically include a filter head with inlet and outlet ports and a spin-on filter element. They are traditionally installed with the filter head located above the filter element (the filter element is screwed on from the bottom). During use, the filter elements accumulate fluid within the filter element housing. During replacement of traditionally-mounted spin on filters, the filters entrap working fluid. Special care must be taken during filter replacement to avoid excessive spillage.
There have been previous attempts to install the filters in inverse orientation (i.e., spin-on filter installed on top of the filter head). While such installations may result in some draining of the filter element by gravity, mere inverse installation still presents a high risk of spillage of fluid remaining in the filter element and/or filter head during the filter replacement.